To find the implicit derivative, we'll use the chain rule and product rule. It's important to remember that when differentiating a #y# term, a #dy/dx# term will be spit out thanks to the chain rule.
#d/dx[-3=xye^(x-y)]#
#0=ye^(x-y)d/dx[x]+xe^(x-y)d/dx[y]+xyd/dx[e^(x-y)]#
Find each derivative.
#d/dx[x]=1#
#d/dx[y]=dy/dx#
#d/dx[e^(x-y)]=e^(x-y)d/dx[x-y]=e^(x-y)(1-dy/dx)=e^(x-y)-e^(x-y)dy/dx#
Plug them back in and solve for #dy/dx#.
#0=ye^(x-y)+xe^(x-y)dy/dx+xye^(x-y)-xye^(x-y)dy/dx#
#-xye^(x-y)-ye^(x-y)=dy/dx(xe^(x-y)-xye^(x-y))#
#(-xye^(x-y)-ye^(x-y))/(xe^(x-y)-xye^(x-y))=dy/dx#
#dy/dx=(e^(x-y)(-xy-y))/(e^(x-y)(x-xy))#
#dy/dx=-(y(x+1))/(x(1-y))#